Exergonic Chemical Reaction
chemical reaction that releases energy. breaking polymers. -ΔG
Endergonic Chemical Reaction
chemical reaction that requires input of energy. building polymers. +ΔG
ΔG
change in free energy and the ability to do work
Entropy
measure of disorder
ΔG Formula
ΔG = ΔH - (T)ΔS
ΔH
change in enthalpy
ΔS
change in entropy
T
absolute temperature in K
K
C + 273 degrees
-ΔG
loss of energy and is spontaneous (exergonic)
+ΔG
gain in energy and is non-spontaneous (endergonic)
ΔG decreases
as cells move towards equilibrium
Calls are not in equilibrium
because cells are in an open system
catabolic pathway
in a cell releases free energy in a series of reactions
where does necessary energy come from?
coupling exergonic reactions (releasing energy) with endergonic reactions (needing energy)
the kind of system that organisms are
endergonic
Energy is needed for
synthesis (biomolecules), reproduction, active transport, movement, temperature regulation
ATP
an energy currency (adenosine triphosphate)
Energy is released from ATP
when the terminal phosphate bond is broken
phosphorylation
transferring a phosphate group to some other